$ chsh -s /bin/zsh
zsh: command not found: chsh

$ ls -ahl /usr/bin/ | grep chsh
-rwxr-xr-x   1 root root     16K Jul 27 21:02 lchsh

[ec2-user@ip-172-31-10-10 ~]$ sudo yum install util-linux-user

[ec2-user@ip-172-31-10-10 ~]$ chsh
Changing shell for ec2-user.
New shell [/bin/bash]: ...